JOURNAL OF HEALTH AND POLLUTION EASA and FAA Research Findings and but advised they were too busy to fnd a speaker or to attend. Actions—Cabin Air Quality FAA Susan Michaelis In 1994 the FAA provided evidence to the US Senate hearings on airliner CAQ advising that “all of the studies University of Stirling, Stirling, UK confrm to us that the air quality aboard an aircraft is at least as good as that commonly found in many KEYWORDS other indoor workplaces or offce environments.”1 cabin air, environmental control system, oil contamination, fume event The committee reported that “despite fndings of various studies that airliner cabin air is generally safe for healthy ABBREVIATIONS APU Auxiliary power unit people”, concerns continued to be voiced by fight CAQ Cabin air quality attendants and passengers.1 EASA European Aviation Safety Agency FAA Federal Aviation Administration A 2001 review of cabin air quality undertaken by the GCAQE Global Cabin Air Quality Executive US National Research Council (NRC) found that oil, OPC Organophosphate compounds hydraulic fuids and their decomposition products posed TCAC Technical cabin air contaminations a moderate concern.2 Recommendations included for TCP Tricresyl phosphate the FAA to rigorously demonstrate the adequacy of the Federal Aviation Regulations (FARs) related to CAQ ABSTRACT and for it to revise standards to protect the health and A brief summary of the historical and recent initiatives undertaken comfort of crew and passengers if required. The FAA by two of the key aviation regulators, EASA and the FAA is outlined was recommended to investigate and publicly report below. This will put into context their roles in the ongoing international aircraft cabin air quality issue. on the need for and feasibility of installing air-cleaning equipment for removing particles and vapors from the air supplied by the environmental control system (ECS) on all aircraft to prevent or minimize the introduction of contaminants into the passenger cabin during both INTRODUCTION normal operation and during air quality incidents. Additionally the FAA was recommended to require The Global Cabin Air Quality Executive (GCAQE) carbon monoxide (CO) monitor in the supply air ducts presented the historical and current key actions and to establish procedures for responding to elevated undertaken by the Federal Aviation Administration (FAA) CO levels. It was also recommended that the FAA and European Aviation Safety Agency (EASA) in relation collect data related to health and air quality incidents to to aircraft air supplies contaminated by engine-generated determine if a relationship existed between health efects compounds via the aircraft bleed air system. or complaints and CAQ. The GCAQE undertook this initiative as EASA, the The 2002 FAA response to the NRC was extensive and European aviation regulator had agreed to present their advised that “FAA rulemaking may not have kept pace most recent research, but after agreeing to participate, with public expectation and concern about air quality and EASA withdrew from both attending and presenting does not afford explicit protection from particulate matter at the conference at short notice. The FAA, the US and other chemical and biological hazards.”3 The FAA aviation regulator was asked to present their activities reported that it would establish an Aviation Rulemaking on the cabin air quality (CAQ) topic in February 2017, Advisory Committee (ARAC) to review the existing journalhealthpollution.org J Health Pollution 24: (191201) 2019 S69 JOURNAL OF HEALTH AND POLLUTION standards related to the CAQ and if found inadequate A joint NASA/FAA and USAF VIPR (Vehicle Integrated they would propose revisions and/ or new standards. Propulsion Research) project was established in 2011 The assessment was to be fairly extensive, suggesting and consisted of three parts, some of which related the air quality regulations may evolve into a more directly to aircraft bleed air contamination. For example comprehensive standard that adopts applicable parts Jones et al. reported that oil contamination in the of an existing consensus standard for environmental compressor will result in a fog of very fne droplets health. None of the NRC recommendations were met (10-150 nm) in the bleed air “under most operating and the ARAC committee was never established and was conditions.”7 It was therefore suggested that “the postponed indefnitely.4 development of sensors for detecting oil contamination in aircraft bleed air should focus on ultrafne particle In 2003 US public law 108-176 directed the FAA to detection and sensing of low contamination levels undertake studies recommended by the NRC related may require sensitivity to extreme ultrafne particles 10 to ozone, pesticides, analysis for contamination of air nanometers and smaller.”7 supply duct flters and the establishment of a reporting system.5 The FAA Center of Excellence was established In 2012 the FAA modernization Reform Act, H.R 658 in 2003 with funding through to 2013. This involved legislated a study of bleed air quality in aircraft cabins numerous studies undertaken by the Airliner Cabin and research and development for cleaning and Environment Research (ACER) group, which became monitoring technologies for the engine and auxiliary Research in Intermodal Transport (RITE) and the power unit (APU) generated bleed air.8 This additionally Occupational Health Research Consortium in Aviation involved identifying oil based and hydraulic and other (OHRCA). The ACER-RITE/OHRCA funded studies from toxins in the bleed air supply, to determine the specifc 2003 to 2013 included in excess of $23 million in FAA amount and duration of toxic fumes in the cabin air grants and $28 million in matched industry funding. that constitutes a health risk to passengers, develop The studies included areas such as recirculation flters; a systematic reporting standard for smoke and fumes incident monitoring and reporting; medical protocol for events in aircraft cabins and to identify potential health bleed air contamination; cabin fow dynamic models risks to individuals exposed to toxic fumes during fight. and sensors; contaminant transport in aircraft; sensors The FAA was to require domestic air carriers to allow and prognostics to mitigate bleed air contamination; monitoring of the air in a way that imposes no signifcant on-board monitoring and measurement methods; efect costs on the carrier and does not interfere with the of partial pressures on passengers, ozone and fame normal operation of the aircraft. The FAA responded to retardants. In relation to the study addressing exposures Congress in 2013 as directed.9 The required activities to oil fumes and reported ill health, the FAA funded the were rejected by the FAA as it considered the work was work but failed to compel airlines to participate, so no already undertaken or not required. The FAA advised defnitive conclusions could be drawn.4 cabin air contamination events were too infrequent, the potential toxicity was speculative and that common In 2004, the FAA published an airworthiness directive standards for cabin air contaminants were lacking, thus (AD) involving inspection and cleaning practices on inhibiting advanced cleaning and detection technologies. the BAe 146 series aircraft. The AD was reported as The FAA reported it would “continue to consider cabin “necessary to prevent impairment of the operational skills safety risk and sponsor research in this area appropriate and abilities of the fightcrew caused by the inhalation to the risk level.”9 of agents released from oil or oil breakdown products, which could result in reduced controllability of the The US Congress passed a further law under the FAA airplane.”6 Reauthorization Act of 2018.10 This included making educational materials available via the FAA website journalhealthpollution.org J Health Pollution 24: (191201) 2019 S70 JOURNAL OF HEALTH AND POLLUTION for pilots, fight attendants and maintenance workers In such cases it was considered that existing on how to respond and report smoke and fume procedures and equipment, including oxygen masks, incidents onboard aircraft. The FAA was also directed were sufcient to mitigate any potential safety risk; to undertake research to develop techniques to monitor • The minor ‘nuisance’ of temporary bad smell the bleed air under ACER, including: identifying and events—due inappropriate maintenance or measuring the constituents and levels from bleed mechanical failures—were acknowledged as under- air events; assessing potential health efects of such reported and not considered a threat to aviation constituents on passengers and air crew; identifying air safety. The frequency was unknown, but suggested supply monitoring and warning systems for bleed air to be less common than one in 10,000 fights. contamination and potential techniques to prevent fume events. The FAA was required to report back to Congress The CRD also stated that a causal relationship not later than 18 months on the feasibility, efcacy, and between reported health efects and oil / hydraulic fuid cost-efectiveness of certifcation and installation of contamination was not yet established. Therefore, with systems to evaluate bleed air quality. no conclusive scientifc evidence available the Agency was unable to justify a rulemaking task to change Additionally, in 2018, the FAA issued a Safety Alert for existing designs or certifcation specifcations. EASA Operators (SAFO).11 The SAFO was issued “to identify a advised health efects were